All part numbers are in the video. These are great engines, unfortunately these head gasket failures are very common. Warped aluminum castings are the root cause but a good OWM gasket can seal the deal for an impressive duration
awesome job, great tips on the oil filter and rocker bolt slot placement, nice property looks like a corn field in the back ground ..blessings to all !!
I have 1986 scag super z with a Kohler cv22. I pulled the head today. First time since new. I'm pretty impressed with this engine and mower for that matter.
Thank you for this video. My neighbor thought i had a bad muffler as it was louder than normal. I had oil spitting out the valve covers, so it looks like it is time. This is good, i needed a reason to drink more beer. 😊
Thank you, thank you, thank you.. This is how a "how to" video should be done! Clear, easy to hear voice with step by step instructions. No moving camera or filming with a cellphone in portrait mode! Showing and telling each part# being replaced. The Kohler's are known for head gasket failures overtime. Love the fact you mention the importance of the air cooled bonnet and head fin cleaning. The motors suck in all that fine debris and over time cause head "hotspots", which lead to head warping. Also love the fact you have the foresight to replace things that should be while your in there! Bravo..........
wow !! bridgeport machine..awesome. i was born in bridgeport ct. , a time when made in usa meant something to the world and the world looked up to the usa...stay awesome mate ...great video ..right to the point - mates like yourself give us " hope " ..... a usn vet !!
Thank you for your service and thank you for your comment. You are right this country is not on a good path, its very sad. I am happy to own one of these world class machines I plan to have it for the rest of my life.
Im going to try to put new gaskets on mine tomorrow , i finish concrete for a living but love to work on small engines on weekends, i just got this 95 exmark lazer z, w/ CH25S, it loses alot of power when I engage pto also is burning or leaking oil i cant wait to tear it down, Thanks for sharing all of your knowledge, and tips,
Was your original part number for jead gasket 24 041 37s ? Do yhe jufs come off? Ive got oil leaking both sides around lower head, liquid oil shouldn't be leaking from head
Thx for the video! good job! Question : Do the knobby Tires on your Exmark help with slipping on inclines etc It rains a lot in Hawaii. looking forward to your reply,
Yes! That's exactly why I got them. I found that the factory tires slip very easy and I was getting stuck often in the wetter season. These tires never get stuck and climb slopes very well. They don't tear up the grass if you are careful otherwise. I recommend them. They also ride smoother since they are for an ATV. I run them very low pressure so they offer some suspension.
Cool vid. I have a Kohler command 20 I plan on doing the same thing to. What machine are you using to resurface the heads? Also on reassembly, does cylinder 1 have to be at tdc or it doesn't matter?
I have a Lazer Z with a Kohler Ch25 on it. Was given to me for free will turn over and start but real hesitant then it pops real loud and dies . What do you think rebuild or what ?
Excellent video! At 7:46 to 9:04 you show the alignment of the rockers. I'm doing an entirely new #1 head on mine, but the slot for the rocker pivots isn't there on the new head. Looked on the old head, and the old one doesn't have it either! So how should I align the rockers and make sure they don't twist?
I recently learned that some don’t have that notch. Just line it up by eye and torque it and all will be well. They won’t twist naturally. I noticed that the Honda GX v twins are very similar to these kohler and they have fully floating rockers with no issue.
It’s my experience that blocks warping is worse than heads. Because of the heat is say. But most 1st time head removal I’ll deck head’s and block. But they are good 3000 hr engines
You’re supposed to bleed down the hydraulic lifters on these before reassembly, I know it sounds the opposite of car lifters, but you can bend pushrods from coil bind. The spring inside opens the lifter all the way and there’s still enough oil inside them to hydro lock and bend your pushrods. I got a free Command 27hp engine with 900hrs from somebody doing that and thinking the engine was toast. 😊
@@spankranchgarage I have a 2004 CV730 25 horsepower has hydraulic lifters, no adjustment. I put my heads on and slowly turned the engine over . The lifters will bleed down. It takes about an hour turn engine until one valve is fully open. Let it bleed down about 15 minutes then turn until another valve opens. About 15 minutes for each valve . No Valve adjustment
They’re basically a lot like car engines from the 60’s hydraulic flat tappet lifters, car style cam, valve gear and rockers. That’s why they last. The power output is very low compared to a car engine which is how they survive with bad cooling etc. The 725cc twins make anywhere from 23-27hp depending on testing type which is equivalent to a Chevy 350 making 196hp.
May I ask at 3K hours why you didn’t replace the rings since you had it all apart. Glad to know the heads warp on this engine since I have the same one. Great video. Sure wish I had a milling machine. Luckily I have a friend that owns a machine shop.
Absolutely fantastic video. Getting ready to do this on my 23 year old Exmark Laser Z with the same problem. Oil spilling from the top of engine when running so I assume it’s a blown head gasket. The only thing I’m worried about is the milling. Probably will need to find a local shop for that.
Thanks! If you have a nice flat surface like an old window glass or a table saw, you can glue some sand paper down to it and move the head in a figure 8 motion until it is flat. This method will work just takes some time and physical work.
@Gabe Bercz, mine started spitting out last week. So I'll be starting mine soon as well. I have a local engine builder that will mill down heads. I have also done the flat sandpaper trick.
There’s also a “valley pan” near the PCV system that has full oil pressure where the hydraulic lifters get their oil supply, that is more common to leak quite a bit of oil externally than the head gaskets.
I got a question, I have the same engine, when I remove both the spark plugs, I can easily turn it with the battery & started motor. But when I put the spark plugs back in, it struggles to turn, it slowly turns but does not have enough energy to turn fast. What could be my problem here, I am not able to get it turn fast and start the engine ? This mower is also 20 years old and I got it from someone who had stored it in a bad garage as the person who rode it died. I added new oil and filter. Sparks are there but I can get it turning fast. Please suggest me.
I’d check battery starter and solenoid connections. Make sure the starter is getting the voltage it needs to draw the current it requires. If thats not it I’d be looking into a weak starter or a compression release issue in the engine
Someone has their parking brake safety switch bypassed lol. What are the valve gaps on these engines. Cant find mine anywhere. Kohler command 27hp sideshaft
That covers the V twins from 22 to 28 horsepower, the 30 and up use different Torque, and a bigger oil filter. Never use a small oil filter on the bigger engine. They will block the oil to the bearings.
@SpankRanch Garage I wanted to ask before I start pulling this apart if you recognize this issue. Mine was running great then shut off just like it ran out of fuel. I cranked it over no start no noises. I sprayed starter fluid into intake and it cranked but had a knocking sound. I checked compression and had good compression. I removed valve covers and everything looks good and is operating properly. I even cranked it over with plugs out and valve covers off and no noises, sounds very smooth? I am thinking a sheared key? Idk why it won't start via fuel pump but will starter fluid unless the flywheel is way off, idk....lol. Your opinion would greatly be appreciated since you are familiar with this engine. Thanks in advance.
@SpankRanch Garage definitely has great spark, just won't start unless I spray starter fluid in carb....my 1st thought was out of gas, fuel pump or filter but has fuel too. When it starts its a loud engine knocking
@@spankranchgarage On your video it looks like there is a steel flame ring around the cylinder hole in the gasket. Must be an industrial grade motor? My gaskets were nothing but asbestos/ fiber! Kohler saved a dollar!
@@glennsprague8535 That's disappointing to hear. The kohler command series are mostly used in industrial/commercial. Maybe yours is a different series. I havent worked on any of those.
@@0tink9 haha youtube has a major glitch right now, my comments are not showing up for some reason. I think maybe youtube caught on and had to force others to comment first 😝
